diff --git a/include/nuttx/nx/nx.h b/include/nuttx/nx/nx.h
index 1c705e5aa4f31b6ddfb421044b0c96e80edb7fd9..3198baf7f1ed2b712063ede9aa1d0bbfa7f321c1 100644
--- a/include/nuttx/nx/nx.h
+++ b/include/nuttx/nx/nx.h
@@ -103,7 +103,8 @@ struct nx_callback_s
    *   rect - The rectangle that needs to be re-drawn (in window relative
    *          coordinates)
    *   more - true:  More re-draw requests will follow
-   *   arg  - User provided argument (see nx_openwindow, nx_constructwindow)
+   *   arg  - User provided argument (see nx_openwindow, nx_requestbkgd,
+   *          nxtk_openwindow, or nxtk_opentoolbar)
    *
    * Returned Value:
    *   None
@@ -127,7 +128,8 @@ struct nx_callback_s
    *            the overall display
    *   bounds - The bounding rectangle that the describes the entire
    *            display
-   *   arg    - User provided argument (see nx_openwindow, nx_constructwindow)
+   *   arg  - User provided argument (see nx_openwindow, nx_requestbkgd,
+   *          nxtk_openwindow, or nxtk_opentoolbar)
    *
    * Returned Value:
    *   None
@@ -149,7 +151,8 @@ struct nx_callback_s
    *   hwnd    - Window handle
    *   pos     - The (x,y) position of the mouse
    *   buttons - See NX_MOUSE_* definitions
-   *   arg     - User provided argument (see nx_openwindow, nx_constructwindow)
+   *   arg  - User provided argument (see nx_openwindow, nx_requestbkgd,
+   *          nxtk_openwindow, or nxtk_opentoolbar)
    *
    * Returned Value:
    *   None
@@ -171,7 +174,8 @@ struct nx_callback_s
    *   hwnd - Window handle
    *   nch  - The number of characters that are available in ch[]
    *   ch   - The array of characters
-   *   arg  - User provided argument (see nx_openwindow, nx_constructwindow)
+   *   arg  - User provided argument (see nx_openwindow, nx_requestbkgd,
+   *          nxtk_openwindow, or nxtk_opentoolbar)
    *
    * Returned Value:
    *   None
@@ -458,7 +462,7 @@ EXTERN int nx_closewindow(NXWINDOW hwnd);
  * Input Parameters:
  *   handle - The handle returned by nx_connect
  *   cb     - Callbacks to use for processing background window events
- *   arg    - User provided argument (see nx_openwindow, nx_constructwindow)
+ *   arg    - User provided value that will be returned with NX callbacks.
  *
  * Return:
  *   OK on success; ERROR on failure with errno set appropriately
@@ -703,7 +707,8 @@ int nx_setbgcolor(NXHANDLE handle,
  * Input Parameters:
  *   hwnd   - The window within which the move is to be done
  *   rect   - Describes the rectangular region to move
- *   offset - The offset to move the region
+ *   offset - The offset to move the region.  The  rectangular region will be
+ *            moved so that the origin is translated by this amount.
  *
  * Return:
  *   OK on success; ERROR on failure with errno set appropriately
diff --git a/include/nuttx/nx/nxtk.h b/include/nuttx/nx/nxtk.h
index 0e066359afd55b67b4922fccc928bf1311f520d5..ae11d565e3ef9a94e6e885908a3ce401e8378f7c 100644
--- a/include/nuttx/nx/nxtk.h
+++ b/include/nuttx/nx/nxtk.h
@@ -320,7 +320,8 @@ EXTERN int nxtk_fillcirclewindow(NXWINDOW hfwnd,
  *            This must have been previously created by nxtk_openwindow().
  *   rect   - Describes the rectangular region relative to the client
  *            sub-window to move
- *   offset - The offset to move the region
+ *   offset - The offset to move the region.  The  rectangular region will be
+ *            moved so that the origin is translated by this amount.
  *
  * Return:
  *   OK on success; ERROR on failure with errno set appropriately
@@ -516,7 +517,8 @@ EXTERN int nxtk_fillcircletoolbar(NXWINDOW hfwnd,
  *            nxtk_openwindow().
  *   rect   - Describes the rectangular region relative to the toolbar
  *            sub-window to move
- *   offset - The offset to move the region
+ *   offset - The offset to move the region.  The  rectangular region will be
+ *            moved so that the origin is translated by this amount.
  *
  * Return:
  *   OK on success; ERROR on failure with errno set appropriately